Loggerhead sea turtles released into Indian River Lagoon

Turtles used for fishing net research

A loggerhead sea turtle is released into the water at Sebastian Inlet.

MELBOURNE BEACH, Fla. - These reptilians can really draw a crowd.

More than 100 people showed up to set free 28 threatened loggerhead sea turtles Monday, according to Local 6 news partner Florida Today.

Parents held up their children and their smartphones to catch a glimpse as federal biologists and volunteers released the turtles into the Indian River Lagoon, a few miles south of Sebastian Inlet.

The turtles had been used in research trials in Panama City, where biologists watch them swim through various nests to learn how best to design special escape hatches for fishing nets that enable turtles to slip free.

Marine biologists want to make fishing nets more efficient at catching fish and shrimp without also capturing turtles.

Shrimp nets are one of the main causes of sea turtle deaths. The turtles drown in the nets when they can't escape and reach the surface for air.

About 20 years ago, it took three or four minutes for a sea turtle to slip out of fishing nets, said Ben Higgins, a sea turtle researcher with the National Oceanic and Atmospheric Administration. Through research into net design, that has improved to 14 seconds for a turtle to escape, Higgins said.

"The turtles are getting out of the nests so fast now it's hard to keep up with them," Higgins told the crowd that had gathered at Inlet Marine before caravanning down State Road A1A to the release site.

Higgins had driven the turtles nine hours from Panama City in a Budget rental truck.

These turtles were dug up at Melbourne Beach three years ago as eggs then raised at NOAA's Galveston, Texas, research laboratory. From there, the turtles were taken to Panama City for the net experiments.

For research purposes, most of the turtles only pass through a net once. Biologists want to know how turtles that have never been exposed to a net before react to being caught. The researchers use juvenile turtles because those have the most trouble escaping fishing nets. The 3-year-old turtles weigh 20 to 30 pounds.

NOAA requires fishermen to put a $250 to $500 "turtle excluder device" on their nets. The device is a grid of bars with an opening at the top or bottom of the net. The grid is fitted into the neck of a shrimp trawl.

Small animals such as shrimp pass through the bars and are caught in the bag end of the trawl. When sea turtles and other larger animals enter the trawl they hit the grid bars and get ejected through the opening.

Scientists also had taken tiny tissue samples from these turtles' flippers to study how sea turtle cells react to certain marine pollutants. Among other things, they want to know how sea turtle are impacted by oil spills and dispersants, such as those from the BP oil spill in 2010.

Biologists don't anticipate any ill effects to the turtles from the recent brown tide algae bloom in the lagoon and haven't seen an increase in the rate of turtles dying or getting stranded.

"We have no evidence of elevated strandings," said Meghan Koperski, an environmental specialist with Florida Fish and Wildlife Conservation Commission.

Loggerheads, a federally threatened species, are among the most plentiful of the five types of sea turtles that nest in Florida.

The beach at Archie Carr National Wildlife Refuge has one of the highest density of sea turtle nests in the world, biologists say. Globally, however, loggerheads have struggled in recent years against long-lasting red tides, dune destruction from coastal development and a mysterious and often fatal disease that makes them anemic, malnourished and sluggish.

Only one in 1,000 hatchlings lives to adulthood.

Children and their parents waded knee deep in the lagoon, carrying one turtle at a time in plastic bins. The turtles dashed out of the tipped crates, wasting no time as they headed for open water.

"I love sea turtles," Christina Wilberg, a marine science teacher at Heritage High School in Palm Bay, said as Higgins held up a flipper-flapping turtle in the back of the Budget rental truck. "As soon as you put them in the water, they just kind of take off."The turtle twisted, mouth agape, ostensibly yearning for the sea.